io.burt.jmespath

Interface Adapter<T>

All Superinterfaces:

Comparator<T>, JmesPath<T>

All Known Implementing Classes:

BaseRuntime, JcfRuntime

public interface Adapter<T>
extends JmesPath<T>, Comparator<T>

An adapter helps the JMESPath parser and interpreter work with a JSON-like structure without having to know how it works. Implement this interface to make it possible to query any JSON-like structure with JMESPath.

Method Summary

Modifier and Type	Method and Description
T	createArray(Collection<T> elements) Returns an array value with the specified elements.
T	createBoolean(boolean b) Returns a boolean value containing the specified boolean.
T	createNull() Returns a null value (not Java null).
T	createNumber(double n) Returns a number value containing the specified floating point number.
T	createNumber(long n) Returns a number value containing the specified integer.
T	createObject(Map<T,T> obj) Returns an object value with the specified properties.
T	createString(String str) Returns a string value containing the specified string.
FunctionRegistry	functionRegistry() Returns a function registry that can be used by the expression compiler to look up functions.
T	getProperty(T value, String name) Deprecated.
T	getProperty(T value, T name) Returns the value of a property of an object.
Collection<T>	getPropertyNames(T value) Returns all the property names of the given object, or an empty collection when the given value does not represent an object.
T	handleArgumentTypeError(Function function, String expectedType, String actualType) Throws an exception or returns a fallback value when a type check fails during a function call evaluation.
boolean	isTruthy(T value) Returns true when the argument is truthy.
NodeFactory<T>	nodeFactory() Returns a node factory that can be used by the expression compiler to build the interpreter AST.
T	parseString(String str) Parse a JSON string to a value.
List<T>	toList(T value) Converts the argument to a List.
Number	toNumber(T value) Converts the argument to a Number, or null if the argument does not represent a number.
String	toString(T value) Converts the argument to a String.
JmesPathType	typeOf(T value) Returns the JSON type of the argument.

Methods inherited from interface io.burt.jmespath.JmesPath

compile

Methods inherited from interface java.util.Comparator

compare, comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Method Detail

parseString

T parseString(String str)

Parse a JSON string to a value. May throw exceptions when the given string is not valid JSON. The exact exceptions thrown will depend on the concrete implementation.

toList

List<T> toList(T value)

Converts the argument to a List. When the argument represents an array the list will contain the elements of the array, when the argument represents an object the result is a list of the object's values and for all other types the result is an empty list.

toString

String toString(T value)

Converts the argument to a String. When the argument represents a string its string value is returned, otherwise a string with the value encoded as JSON is returned.

toNumber

Number toNumber(T value)

Converts the argument to a Number, or null if the argument does not represent a number.

isTruthy

boolean isTruthy(T value)

Returns true when the argument is truthy. All values are truthy, except the following, as per the JMESPath specification: false, null, empty lists, empty objects, empty strings.

typeOf

JmesPathType typeOf(T value)

Returns the JSON type of the argument. As per the JMESPath specification the types are: number, string, boolean, array, object, null.

See Also:

JmesPathType

getProperty

@Deprecated
T getProperty(T value,
                          String name)

Deprecated.

Returns the value of a property of an object. The first argument must be an object and the second argument may be the name of a property on that object. When the property does not exist a null value (not Java null) is returned.

getProperty

T getProperty(T value,
              T name)

Returns the value of a property of an object. The first argument must represent an object and the second argument may be the name (which must be a string value) of a property of that object. When the property does not exist or represents null a null value (but not Java null) is returned.

getPropertyNames

Collection<T> getPropertyNames(T value)

Returns all the property names of the given object, or an empty collection when the given value does not represent an object. The property names are always string values.

createNull

T createNull()

Returns a null value (not Java null).

createArray

T createArray(Collection<T> elements)

Returns an array value with the specified elements.

createString

T createString(String str)

Returns a string value containing the specified string.

createBoolean

T createBoolean(boolean b)

Returns a boolean value containing the specified boolean.

createObject

T createObject(Map<T,T> obj)

Returns an object value with the specified properties. The map keys must all be string values. Creating nested objects is not supported.

createNumber

T createNumber(double n)

Returns a number value containing the specified floating point number.

createNumber

T createNumber(long n)

Returns a number value containing the specified integer.

handleArgumentTypeError

T handleArgumentTypeError(Function function,
                          String expectedType,
                          String actualType)

Throws an exception or returns a fallback value when a type check fails during a function call evaluation.

functionRegistry

FunctionRegistry functionRegistry()

Returns a function registry that can be used by the expression compiler to look up functions.

nodeFactory

NodeFactory<T> nodeFactory()

Returns a node factory that can be used by the expression compiler to build the interpreter AST.